A kind of wavefront curvature sensor with diffraction grating and application

The basic principle of wavefront curvature sensor(WFS) is described, and the strongpoints and shortcomings of traditional schemes are analyzed. As a novel WFS, the wavefront curvature sensor comprising a diffraction grating(DGWFS), which consist a defocus grating and lens, and can measure the light intensity distribution at the two defocused spots simultaneity , has the advantage of realization easily, adjustment expediently, low cost, and so on. The DGWFS has a wide application in astronomy, measurement, laser, optical component testing etc. Its principle is analyzed. Two kinds of phase retrieval arithmetics of wavefront curvature sensor are analyzed by comparison. Besides, the latest applications of wavefront curvature sensor are generally presented. Finally a novel method for measurement on solid-state laser thermal lens utilizing DGWFS is presented. © 2009 SPIE.